Erasure codes may provide a storage efficient alternative to replication based redundancy in (networked) storage systems. They however may entail high communication overhead for maintenance, when some of the encoded fragments are lost and need to be replenished. Such overheads may arise from the fundamental need to recreate (or keep separately) first a copy of the whole object before any individual encoded fragment can be generated and replenished.
Therefore, there is a need for a way to generate and replenish any individual encoded fragment without having to acquire first a copy of the whole object.